I have ten 12" ball bungee cords that I have strung together for a clothesline. They are much stronger and more adjustable than the clotheslines I have seen at REI or online. Smaller space? Remove a cord or two.
Obviously this isn't for a long weekend trip.

It's for the two and three + month trips where it is a huge help with the things I want to hand wash so they aren't ruined.